Genetic testing is the examination of a person’s genetic makeup, also referred to as DNA. These tests are done by analyzing small samples of blood or body tissues. Most of us have read or heard about the purposes of genetic testing for medical purposes, but there is a large variety of reasons to look at a person’s genetic makeup. Here is a list of different ways genetic tests are used and the benefits of these tests.
Clinical Genetic Testing
Clinical genetic testing is the the laboratory analysis of DNA or RNA to aid in the diagnosis of disease. According to Labs On Line, “There are four basic tests that are included in this testing: Presymptomatic, diagnostic, carrier screening and prenatal screening.”
The benefits of presymptomatic testing is that it can identify the presence of genes that cause disease even if the symptoms are not present. This early warning system can help determine current or future medical treatment and define lifestyle choices to ward off or delay the symptoms.
Diagnostic genetic testing is performed when symptoms sufficiently suggests a genetic disorder. It is yet another preemptive strike against a disease and can aid in timely medical treatment.
Carrier screening is performed when two individuals who want to have a child and have an autosomal or X-linked recessive gene and that will produce a serious condition when combined in a child. For example, cystic fibrosis is an autosomal recessive trait. Carrier screening diagnosis along with discussions with their medical provider will help couples make informed decisions.
Prenatal testing is available for detecting abnormalities in the genes of a fetus. Spina bifida and Down syndrome are two genetic disorders that are commonly screened for in this process.
Pharmacogenomics
Pharmacogenomics is the assessment or examination of gene interaction with drugs. According to Labs on Line, “There have been cases regarding individuals who are given a certain therapeutic drug to treat symptoms or to keep symptoms from occurring in which the individual has a very violent reaction to the drug or feels no affect whatsoever. Many times this happens because of the genetic makeup of the individual. The study of this phenomenon is called pharmacogenomics or pharmacogenetics.” The value of having results of this test available to the treating physician can easily make the difference between or death.
Identity Testing
Sometimes referred to as “DNA testing,” identity testing is used for criminal investigations of forensics studies. The test is used to identify a suspect in a criminal investigation by comparing the DNA found at a crime scene to that of “persons of interest.” When an individual is convicted of the crime, his or her DNA polymorphisms are put into a data bank system that is accessible by law enforcement officials. This system is called Combined DNA Index System (CODIS). In addition to solving crimes, identity testing also has cleared suspects and convicted individuals who have been wrongfully accused of a crime.
Parentage Testing
Often referred to as paternity testing, parentage testing is used to determine or verify the biological parents of children. Generally at least 99 percent certainty is required to validate the test and is often used in courts of law.
Tissue Typing
Tissue typing is a genetic testing process that analyzes of genetic material for results in fewer rejection reactions and the chance for successful organ or tissue transplantation.
Infectious Disease Testing
Bacteria and viruses that cause disease are known as infectious agents, and many of them can be identified by using genetic testing procedures. An example of a common use of this testing is the inspection of donor blood for viral contamination prior to a transfusion.
Using Genetic Testing Responsibly
Genetic testing is not without its controversy. We can even buy test kits on-line without the benefit of review from a doctor or genetic counselor. The Mayo Clinic website reminds us that, “Although genetic testing can provide important information for diagnosing, treating and preventing illness, there are limitations. Talking with your doctor or a genetic counselor about what you will do with the results is an important step in the process of genetic testing.”
Sources:
Genetic Testing, Wikipedia: Website
National Institute of Health: How is Genetic Testing Done? Website
Lab Test Online: The Universe of Genetic Testing; Website
The Mayo Clinic: Genetic Testing; Website
